Biology

Plant Transport and Physiology

1,834 Questions

Access a comprehensive set of questions on plant transport mechanisms and physiological adaptations. Topics include water movement, translocation of food, and plant responses to external stimuli. These biology questions are essential for medical entrance exams and other science competitive tests.

Xylem and phloem transportTranspiration and evaporationPlant adaptationsGeotropic and phototropic responsesWater absorption by rootsRespiration in roots

Plant Transport and Physiology Questions

Multiple choice

Phloem is made of which of the following?

Directions: Read the given passage and answer the following question.

Xylem and Phloem. The Xylem is responsible for transporting water and certain nutrients from the root to the rest of the plant. The Phloem carries soluble organic material, i.e. food for the plant, which is produced in the leaves by photosynthesis to the other parts of the plant. The Xylem and phloem are the two types of vascular tissues that are present in plants. They are responsible for transporting water, minerals, food and other organic materials between the roots, stems and leaves of the plant. The Xylem and phloem form vascular bundles with each other, which means that together they are responsible for the efficient transportation of food, nutrients, minerals, and water in the plant, and hence the survival of the plant. Xylem is a type of transport tissue in vascular plants that is responsible for transporting water and certain nutrients from the root to the rest of the plant. Thus, it essentially flows in one direction, that is, from the bottom up to the sky towards the top of the plant. Its main function is to effectively transport water and nutrients from the soil to the various parts of the plant. The word ‘xylem’ is derived from the Greek word ‘xylon’, meaning wood. This is because wood is the best-known xylem tissue which is found throughout the tree. Xylem is a mixture of dead and living tissues, which are non-living at the time of maturity. It is made up of tracheids, vessels, xylem parenchyma, xylem fibres and ray parenchyma. Xylem cells are hard walled cells, which are stacked on top of each other and are mainly found in the center of the stem. Hence, xylem has another function, which is to provide mechanical support to the plant. The Xylem is surrounded by the phloem. The Phloem is the other type of transport tissue in vascular plants. Its main function is to carry soluble organic material, i.e. food for the plant, which is produced in the leaves by photosynthesis to the other parts of the plant. This process is called translocation. To do this effectively it flows both up and down the stem, unlike the xylem, which only flows up. The word ‘phloem’ is derived from the Greek word ‘phloos’, which means bark, as the phloem is the innermost layer of the bark in most trees. The Phloem is made up of sieve cells, sieve tube elements, phloem parenchyma, phloem fibres, and phloem ray cells. It consists of both living and dead soft-walled cells, where the outer phloem is made up of dead cells and the inner phloem is made of living cells.

  1. Vessels

  2. Ray parenchyma

  3. Sieve tube elements

  4. Tracheids
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Phloem is made of sieve cells.

Multiple choice

In which direction does Xylem transport nutrients to plants?

Directions: Read the given passage and answer the following question.

Xylem and Phloem. The Xylem is responsible for transporting water and certain nutrients from the root to the rest of the plant. The Phloem carries soluble organic material, i.e. food for the plant, which is produced in the leaves by photosynthesis to the other parts of the plant. The Xylem and phloem are the two types of vascular tissues that are present in plants. They are responsible for transporting water, minerals, food and other organic materials between the roots, stems and leaves of the plant. The Xylem and phloem form vascular bundles with each other, which means that together they are responsible for the efficient transportation of food, nutrients, minerals, and water in the plant, and hence the survival of the plant. Xylem is a type of transport tissue in vascular plants that is responsible for transporting water and certain nutrients from the root to the rest of the plant. Thus, it essentially flows in one direction, that is, from the bottom up to the sky towards the top of the plant. Its main function is to effectively transport water and nutrients from the soil to the various parts of the plant. The word ‘xylem’ is derived from the Greek word ‘xylon’, meaning wood. This is because wood is the best-known xylem tissue which is found throughout the tree. Xylem is a mixture of dead and living tissues, which are non-living at the time of maturity. It is made up of tracheids, vessels, xylem parenchyma, xylem fibres and ray parenchyma. Xylem cells are hard walled cells, which are stacked on top of each other and are mainly found in the center of the stem. Hence, xylem has another function, which is to provide mechanical support to the plant. The Xylem is surrounded by the phloem. The Phloem is the other type of transport tissue in vascular plants. Its main function is to carry soluble organic material, i.e. food for the plant, which is produced in the leaves by photosynthesis to the other parts of the plant. This process is called translocation. To do this effectively it flows both up and down the stem, unlike the xylem, which only flows up. The word ‘phloem’ is derived from the Greek word ‘phloos’, which means bark, as the phloem is the innermost layer of the bark in most trees. The Phloem is made up of sieve cells, sieve tube elements, phloem parenchyma, phloem fibres, and phloem ray cells. It consists of both living and dead soft-walled cells, where the outer phloem is made up of dead cells and the inner phloem is made of living cells.

  1. Both up and down

  2. Root to sky

  3. Sky to root

  4. Only downwards
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Xylem is a type of transport tissue in vascular plants that is responsible for transporting water and certain nutrients from the root to the rest of the plant. Thus, it essentially flows in one direction, that is, from the bottom up to the sky towards the top of the plant.

Multiple choice

What do we call the process of transportation of water and nutrients in plants?

Directions: Read the given passage and answer the following question.

Xylem and Phloem. The Xylem is responsible for transporting water and certain nutrients from the root to the rest of the plant. The Phloem carries soluble organic material, i.e. food for the plant, which is produced in the leaves by photosynthesis to the other parts of the plant. The Xylem and phloem are the two types of vascular tissues that are present in plants. They are responsible for transporting water, minerals, food and other organic materials between the roots, stems and leaves of the plant. The Xylem and phloem form vascular bundles with each other, which means that together they are responsible for the efficient transportation of food, nutrients, minerals, and water in the plant, and hence the survival of the plant. Xylem is a type of transport tissue in vascular plants that is responsible for transporting water and certain nutrients from the root to the rest of the plant. Thus, it essentially flows in one direction, that is, from the bottom up to the sky towards the top of the plant. Its main function is to effectively transport water and nutrients from the soil to the various parts of the plant. The word ‘xylem’ is derived from the Greek word ‘xylon’, meaning wood. This is because wood is the best-known xylem tissue which is found throughout the tree. Xylem is a mixture of dead and living tissues, which are non-living at the time of maturity. It is made up of tracheids, vessels, xylem parenchyma, xylem fibres and ray parenchyma. Xylem cells are hard walled cells, which are stacked on top of each other and are mainly found in the center of the stem. Hence, xylem has another function, which is to provide mechanical support to the plant. The Xylem is surrounded by the phloem. The Phloem is the other type of transport tissue in vascular plants. Its main function is to carry soluble organic material, i.e. food for the plant, which is produced in the leaves by photosynthesis to the other parts of the plant. This process is called translocation. To do this effectively it flows both up and down the stem, unlike the xylem, which only flows up. The word ‘phloem’ is derived from the Greek word ‘phloos’, which means bark, as the phloem is the innermost layer of the bark in most trees. The Phloem is made up of sieve cells, sieve tube elements, phloem parenchyma, phloem fibres, and phloem ray cells. It consists of both living and dead soft-walled cells, where the outer phloem is made up of dead cells and the inner phloem is made of living cells.

  1. Flow

  2. Photosynthesis

  3. Translocation

  4. Effective transportation
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

"The Phloem is the other type of transport tissue in vascular plants. Its main function is to carry soluble organic material, i.e. food for the plant, which is produced in the leaves by photosynthesis to the other parts of the plant. This process is called translocation." Hence, translocation is the correct answer.

Multiple choice

Which of the following is a function of sieve tubes?

  1. Translocation of minerals and food

  2. Translocation of water

  3. Translocation of minerals and water

  4. Elimination of organic food
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Translocation of food is a function of sieve tubes. Sieve tube elements are a specialised type of elongated cells in the phloem tissue of flowering plants. The ends of these cells are connected with other sieve tube members and together they constitute the sieve tubes.

Multiple choice

Which of the following statements is/are false?

a. The opening and closing of stomatal pores is controlled by the guard cells. b. Green plants take carbon dioxide from air for photosynthesis. c. Cytoplasm is the site of photosynthesis in the cell of a leaf.

  1. Only a

  2. Only a and b

  3. Only b

  4. Only b and c

  5. Only c
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

This is the correct option as this statement is false. Chloroplast is the site of photosynthesis in the cell of a leaf.

Multiple choice

What does climacteric mean?

  1. Sudden increase in respiration during fruit ripening

  2. Sudden premature fall of all the fruits

  3. Shedding of flowers before anthesis

  4. Climax vegetation

  5. Sudden increase in the rate of photosynthesis
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Climacteric refers to the sudden increase in respiration during fruit ripening.

Multiple choice

Why does a plant cell not burst when it is placed in a hypotonic solution?

  1. Due to the presence of cell wall

  2. Due to the presence of cytoplasm

  3. Due to the presence of plasma membrane

  4. Due to the presence of large vacuoles
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Cell walls permit the cells of plants, fungi and bacteria to withstand very dilute (hypotonic) external media without bursting. In such media, the cells tend to take up water by osmosis.

Multiple choice

If a plant cell is placed in deionised water, the water potential of that cell becomes

  1. more positive because the pressure potential becomes more positive

  2. more positive because the osmotic potential becomes more negative

  3. more negative because the pressure potential becomes more negative

  4. less negative because the pressure potential becomes more positive
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

When a plant cell is placed in deionised water, water enters by osmosis, increasing turgor pressure. The cell wall resists expansion, creating positive pressure potential. Osmotic potential becomes slightly more negative due to dilution. The net water potential becomes less negative because the positive pressure potential increase outweighs the osmotic change. This is the classic turgor pressure development in plant cells.